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1
Content available remote Development of nanostructured anti-fouling coatings for hydro plant facilities
Grabowiecki Krzysztof, Krasucki Janusz, Buczko Zofia, Osuchowska Ewa, Olkowicz Klaudia
Journal of Power Technologies
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2021
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Vol. 101, nr 4
226--235
EN
The biofouling is a serious technical issue in hydropower facilities operating in a freshwater environment. The presented novel technology of antifouling coating integrates two functionalities of deposited material - biocidal features of copper and superhydrophobicity of the surface. The well-known, low cost copper electroplating process on the steel surface has been modified to achieve a hierarchical micro/nano scaled surface structure. The significantly reduced wettability of the coating surface in combination with biocidal activity of copper increases the surface resistance to biofouling. The influence of selected electroplating parameters in combination with the pretreatment of the substrate steel surface was investigated. The resulted coating surface was tested for durability under slurry flow conditions. Finally, the large component - the intake water filter of hydropower plant - was subject of field testing and was successfully tested for biofouling resistance.
2
Content available Improving the Water-Repellent and Antifungal Properties of Electrospun Cellulose Acetate Materials by Decoration with ZnO Nanoparticles
Nachev Nasko, Spasova Mariya, Manolova Nevena, Rashkov Iliya, Naydenov Mladen
Fibres & Textiles in Eastern Europe
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2021
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Vol. 29, no. 3 (147)
40--45
EN
Suitable conditions for the preparation of nano- and microstructured materials from cellulose acetate and cellulose acetate/ZnO from solutions/suspensions in aceton/water by electrospinning/electrospraying were found. The materials obtained were characterised by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD) and contact angle measurements. The antifungal activity of the materials obtained against Phaeomoniella chlamydospora, which is one of the main species causing diseases in grapevines, was studied as well. It was found that electrospinning of CA solutions with a concentration of 10 wt% reproducibly resulted in the preparation of defect-free fibres with a mean fibre diameter of ~780 nm. The incorporation of ZnO nanoparticles resulted in the fabrication of hybrid materials with superhydrophobic properties (contact angle 152°). The materials decorated with ZnO possessed antifungal activity against P. chlamydospora. Thus, the fibrous materials of cellulose acetate decorated with ZnO particles obtained can be suitable candidates to find potential application in agriculture for plant protection.
PL
W pracy wskazano odpowiednie warunki do otrzymywania materiałów nano- i mikrostrukturalnych z octanu celulozy i octanu celulozy/ZnO z roztworów/zawiesin w acetonie/wodzie metodą elektroprzędzenia/elektrorozpylania. Uzyskane materiały scharakteryzowano za pomocą skaningowej mikroskopii elektronowej (SEM), dokonano analizy dyfrakcji rentgenowskiej (XRD) oraz pomiarów kąta zwilżania. Zbadano również działanie przeciwgrzybiczne uzyskanych materiałów przeciwko Phaeomoniella chlamydospora, który jest jednym z głównych gatunków wywołujących choroby winorośli. Stwierdzono, że podczas elektroprzędzenia z roztworów CA o stężeniu 10% wag. w sposób powtarzalny otrzymywano włókna wolne od defektów o średniej średnicy ~ 780 nm. Wprowadzenie nanocząstek ZnO zaowocowało wytworzeniem materiałów hybrydowych o właściwościach superhydrofobowych (kąt zwilżania 152°). Materiały z dodatkiem ZnO wykazywały działanie przeciwgrzybiczne przeciwko P. chlamydospora. Stwierdzono, że otrzymane materiały mogą być stosowane w rolnictwie do ochrony roślin.
3
Content available Superhydrophobic MWCNTs/PDMS-nanocomposite materials: Preparation and characterization
Sulym Iryna, Kubiak Adam, Jankowska Katarzyna, Sternik Dariusz, Terpilowski Konrad, Sementsov Yuriy, Borysenko Mykola, Derylo-Marczewska Anna, Jesionowski Teofil
Physicochemical Problems of Mineral Processing
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2019
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Vol. 55, iss. 6
1394--1400
EN
The surface morphology, structure and hydrophobicity of low-and high-molecular weight poly(dimethylsiloxane) (PDMS) fluids physically adsorbed onto multi-walled carbon nanotubes (MWCNTs) at different weight percentages (5, 10, 20 and 40 wt.%), were studied employing X-ray diffraction (XRD), attenuated total reflectanceFouriertransforminfrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM) and measurements of contact angle with water. It was found that MWCNTs agglomerate forming voids between tubes of a broad range, while adsorption of the polymer from a hexane solution results in the expected wrapping of nanotubes withPDMS chains and, further, in filling voids, as represented by SEM data. ATR-FTIR was used to investigate the possible structural changes in the polymer nanocomposites. Based on the contact anglemeasurementsvia water drop shape analysis,MWCNTs/PDMS nanocomposites were characterizedas astable,superhydrophobic materials with the maximum contact angle (CA) equal to 152°at CPDMS=40wt.%.
4
Content available Influence of dodecanol on wetting behavior of superhydrophobic surfaces
Sayfutdinova A. R., Emelyanenko A. M., Boinovich L. B.
Physicochemical Problems of Mineral Processing
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2018
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Vol. 54, iss. 1
131--141
EN
Digital processing of the optical image of a sessile droplet was used to study the influence of dodecanol vapors and condensate on the wettability of superhydrophobic coatings by water. Two types of coatings with very different morphologies were used to estimate the stability of the superhydrophobic state in the presence of dodecanol at different regimes of interaction of tested superhydrophobic coatings with dodecanol vapors, including preliminary condensation of dodecanol inside the substrate pores/grooves at different temperatures, a short-term contact of dodecanol vapor with the superhydrophobic coating with the preliminary deposited water droplets and, finally, a long-term contact between substrate with deposited water droplets and the vapor phase saturated with dodecanol vapor. The set of experimental data indicate only minor variations of water contact and roll-off angles for all regimes studied. Such wettability behavior evidences good persistence of superhydrophobic state in conditions of contact with long-chain alcohol vapors.
5
Powłoki na stali nierdzewnej wytwarzane anodowo oraz metodą CVD z nanostrukturami węglowymi o właściwościach hydrofobowych
Buczko Z., Olkowicz K., Tomassi P., Żółciak T.
Inżynieria Powierzchni
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2018
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nr 2
30--37
PL
Metodą anodowego utleniania stali nierdzewnej i późniejszego nakładania warstw węglowych w procesach CVD otrzymano powłoki o właściwościach hydrofobowych i superhydrofobowych. Modyfikowano parametry procesu CVD i otrzymywano różne struktury węglowe, w tym grafenowe. Warstwy charakteryzowano za pomocą widm Ramana oraz mikroskopii SEM. Zwilżalność powierzchni oceniono badając kąt zwilżania. Próbki zawierające warstwy węglowe wykazywały właściwości hydrofobowe, a te zawierające struktury grafenowe charakteryzowały się kątem zwilżania większym niż 150°, co oznacza właściwości superhydrofobowe.
EN
The method of anodic oxidation of stainless steel and the subsequent deposition of carbon layers in the CVD processes resulted in obtaining the coatings with hydrophobic and superhydrophobic properties. The parameters of the CVD process were modified and various carbon structures, including graphene type ones, were obtained. The coatings were characterised by Raman spectra and SEM microscopy. The wettability of the surface was evaluated by investigating a contact angle. The samples containing carbon coatings showed hydrophobic properties, and those containing graphene structures were characterized by the contact angle greater than 150°, which means superhydrophobic properties.
6
Content available remote Surface morphology and topographical studies of fluorine doped tin oxide as transparent conducting film
Jeyasubramanian K., Gokul Raja T. S.
Archives of Materials Science and Engineering
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2016
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Vol. 78, nr 2
66--70
EN
Purpose: This paper deals about the preparation and characterization of transparent conducting metal oxide doped with fluorine for superhydrophobic applications. Design/methodology/approach: Fluorine doped tin oxide(FTO) have been deposited on glass substrate employing an inexpensive spray pyrolysis route. Uniform coating of thin film was controlled by the parameters like flow rate, exposure duration, temperature of pyrolysis process etc. Findings: Fluorine doped SnO2 was confirmed from FTIR studies. Transparent nature of the coating was evaluated through UV-vis. spectroscopy. Electrical resistivity of the deposited film measured using source meter showed a least resistance of 13 Ω. AFM & SEM analysis revealed the texture of nano SnO2 in the range of 100-300 nm. Unevenness is one of the prerequisite for achieving superhydrophobic nature, which has been explored through AFM results. Practical implications: An attempt has been done to fabricate fluorine doped tin oxide thin film using spray pyrolysis technique may be used for developing super hydrophobic coating application. Originality/value: This study aims to reduce the cost of forming superhydrophobic surfaces on comparison with the process like plasma etching and sensitizing with nanoparticles, etc.
7
Content available A facile approach for the fabrication of superhydrophobic surface with candle smoke particles
Qin D.
Physicochemical Problems of Mineral Processing
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2015
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Vol. 51, iss. 2
501--510
EN
The aim of this communication is to explore a simple and efficient method for fabrication of superhydrophobic surface by candle smoke particles (CSPs). The properties of CSPs before and after the calcination process has been studied by SEM, TEM, TG-DSC, FT-IR and contact angle measurements. The results show that there is a complex mixture of elemental carbon and a variety of hydrocarbons in association with amorphous nanomaterial in CSPs, whose structure and composition leads to superhydrophobic properties. The wetting properties of CSPs can turn from superhydrophobic into superhydrophilic due to characteristic group changes by calcination process. Thus, it is a simple and efficient method to fabricate superhydrophobic or superhydrophilic surface by CSPs at low cost.
8
Content available Fluorokarbofunkcyjne silany jako prekursory materiałów silnie hydrofobowych
Karasiewicz J., Dutkiewicz A., Maciejewski H
Chemik
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2014
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Vol. 68, nr 11
945--956
PL
W artykule opisano metody modyfikacji powierzchni płytek szklanych w celu wytworzenia powłok o własnościach hydrofobowych i superhydrofobowych. Powierzchnię modyfikowano za pomocą związków o niskiej swobodnej energii powierzchniowej, stosując fluorokarbofunkcyjne silany oraz dodatkowo poprzez modyfikację w zolu krzemionkowym, który zwiększał chropowatość powierzchni. Kąty zwilżania powierzchni były wyznaczane goniometrycznie, a morfologia powierzchni za pomocą mikroskopii sił atomowych.
EN
Methods of modification of glass plates aimed at forming hydrophobic and superhydrophobic coatings have been described in the paper. The surface was modified with the use of compounds of low surface free energy by employing fluorocarbofunctional silanes and by performing an addtional modification with silica sol that increased the surface roughness. Water contact angles were determined goniometrically and the surface morphology by means of atomic force microscopy.
9
Content available remote Elastomery silikonowe o zwiększonej hydrofobowości uzyskiwane z mikrotrawionych matryc Si i Al
Żyłka P.
Przegląd Elektrotechniczny
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2013
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R. 89, nr 7
327--329
PL
Hydrofobowość gum silikonowych zależy w silny sposób m.in. od mikrostruktury ich powierzchni. W artykule przedstawiono wyniki prac doświadczalnych zmierzających do zwiększenia hydrofobowości kauczuku silikonowego. W tym celu zastosowano metodę repliki negatywowej z matryc w postaci mikrotrawionego anizotropowo podłoża krzemowego i trawionego elektroerozyjnie podłoża duralowego. Uzyskane repliki silikonowe scharakteryzowano pod względem mikrotopografii powierzchni, jej chropowatości oraz kąta zwilżania dla kropli wody.
EN
Hydrophobicity of silicone rubber depends strongly on its surface properties. The paper presents results of experimental works aimed at obtaining silicone rubber displaying enhanced hydrophobicity. Direct replica method was used for sample manufacturing while anisotropic etched silicon and electro-discharge machined duralumin substrates were employed as templates. Silicone rubber replicas were characterized for surface microtopography, its roughness as well as water contact angle.
10
Content available remote Akrylowe i silikonowe materiały dielektryczne o biomorficznej mikrostrukturze powierzchni
Żyłka P., Moroń L.
Przegląd Elektrotechniczny
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2010
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R. 86, nr 5
279-282
PL
W pracy omówiono aktualny stan badań w zakresie polimerowych materiałów dielektrycznych, których powierzchnie posiadają cechy biomorficzne tzn. naśladują - pożądane w nauce i technice - właściwości organizmów żywych lub materiałów naturalnych. Szczególną uwagę zwrócono na materiały wykazujące „efekt lotosu”, czyli posiadające właściwości superhydrofobowe. Przegląd literatury zilustrowano wynikami prac zmierzających do uzyskania (metodą repliki z pierwowzoru akrylowego) powierzchni gumy silikonowej HTV, wykazującej „efekt lotosu”.
EN
The paper discusses current state of research related to polymeric dielectric materials in which surface displays biomorphic characteristics i.e. it imitates – desirable from scientific and technological point of view – features of living organisms or natural materials. Special attention is paid to superhydrophobic materials displaying “lotus effect”. The concise literature review is illustrated with results of experiments aimed at obtaining (by means of acrylic model replica method) HTV silicone rubber with surface displaying “lotus effect”.
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